Shower apparatus

ABSTRACT

A shower apparatus reduces the effects of water hammer within a portion of a flow route connecting a shower head to a supply, when a flow adjusting mechanism proximal the shower head is operated. The shower apparatus adjusts pressure of a supply fluid dependant upon the degree of throttling of the flow route and the flow adjusting mechanism controls the amount of flow of the supply fluid dependant upon a degree of opening thereof to the discharge end of a shower head. The structure providing the pressure adjustment and the flow adjusting mechanism are each disposed successively from upstream of the flow route, between a shower side flow route provided in a water plug and the shower head or a discharge end of the shower head. The shower apparatus further cushions the pressure against an increase in the internal pressure of the flow route which occurs when the flow route is closed by the flow adjusting mechanism, and is provided as a flow route system capable of cushioning an increase in the internal pressure of the flow route when the flow amount adjusting means is operated. An increase in pressure due to water hammer which occurs when flow of water feeding is terminated is suppressed, preventing the otherwise excessive pressure from acting on respective parts including the shower hose, thereby serving to prolong an original pressure resistance of the shower hose and maintain proper continued function of components downstream of the water plug.

BACKGROUND OF THE INVENTION

This invention relates to a shower apparatus in which a shower headportion thereof contains an opening valve, a flow adjusting valve andthe like and, more particularly, a shower apparatus designed to resistdamage by water hammer or the like which may occur when such valve isclosed.

General types of shower apparatuses provided in bathrooms contain ashower head connected to a hot water/cold water mixing plug through ahose.

Turning-on and stopping of the water flow is carried out by means of aselect handle on a hot water/cold water mixing plug or an opening valveprovided in the shower head as disclosed in Japanese Utility ModelPublication No. Sho 58-53118.

If the opening valve is suddenly closed in the type in which waterfeeding and discharge are carried out on the shower head side, waterhammer occurs in the primary side of the opening valve, i.e., in a flowroute between the hose and the hot water/cold water mixing plug. Ifwater hammer occurs, pressure in the internal flow route rises and atthe same time, the pressure changes suddenly. As a result, deteriorationin pressure resistance of the hose is induced by vibration of the hoseor increase in the internal pressure thereof.

To solve the water hammer problem, it is effective to provide the waterplug side with a pressure responding valve or the like for cushioning anincrease in the internal pressure as disclosed in Japanese Utility ModelPublication No. Sho 58-32753. With the pressure responding valve, achamber sectioned by a diaphragm is made to communicate with the flowroute up to the water discharge device, and the increase in internalpressure which occurs when a valve containing this water dischargedevice is closed is absorbed by deformation of the diaphragm.

As a mechanism for preventing the aforementioned water hammerphenomenon, various methods are already known, and structures forabsorbing or releasing an increase in internal pressure as disclosed inthe preceding patent publication are basic ones.

In addition to the above described mechanism for preventing waterhammer, as disclosed in Japanese Unexamined Utility Model PublicationNo. Hei 6-5588, a pressure adjusting valve for adjusting the pressure ofmixing water to be fed to the shower head is incorporated in the flowroute in the upstream end of the shower hose so that primary sidepressure is not applied to the shower hose when the opening valve of theshower head is closed.

If an opening valve for discharging water and stopping thereof isprovided, the main body of the shower head is held by one hand and theknob of the opening valve is operated by the other hand. In this case,it is preferable from the viewpoint of usability that operations forstopping the discharge of water, and inverse operations, can be carriedout quickly. Thus, a mechanism which opens and closes the flow route allat once by employing a push-button type opening valve is employed so asto quicken valve closure.

If the opening valve closes quickly, the amount of water hammer isincreased and the internal pressure on the hose side in the downstreamend is changed largely all at once, so that loading of the internalpressure to the hose when water hammer occurs is consistently repeated.It is effective to apply the pressure responding valve as disclosed inthe preceding patent publications corresponding to such water hammer.

However, although a diaphragm for absorbing changes in pressure canstabilize pressure in the hose by elastic deformation of the diaphragmeven after the pressure responding valve has been closed, the effectthereof in reducing a rise in pressure just after water hammer occurs islimited. Further, if a valve body is provided which is activated totemporarily expand the volume of the internal flow route incorrespondence with an increase in pressure, and at the same time closethe internal flow route, it is also possible to suppress the increase inpressure which occurs when water hammer occurs. However, after thisvalve body is moved, response to changes in pressure tend to be inferiorto elastic deformation of the diaphragm, so that the effect ofstabilizing the pressure in the hose is consequently reduced.

Although the diaphragm type is suitable for stabilization after a changein pressure, the effect of attenuation of an increase in pressure due towater hammer tends to be inferior. On the other hand, although a solidtype valve body is preferable for attenuation of rise in pressure, it isnot entirely effective for subsequent stabilization of the pressure inthe hose. Thus, no conventional types of pressure responding valvesusing diaphragms or valve bodies are sufficiently effective during theoccurrence of water hammer.

For this reason, a type which contains an opening valve in its showerhead, even though the pressure responding valve is contained in flowroute, is not capable of effectively suppressing an increase in theinternal pressure in the hose at the time water flow is stopped. Thisresults in problems, such as accelerated deterioration due to pressureresistance fatigue of the hose.

On the other hand, in a type which contains a pressure adjusting valvein the flow route in the upstream end of the shower hose, when anopening valve provided in the shower head in the form of a hand-operatedvalve is closed, water hammer occurs in the shower hose, and therebyinduces an increase in internal pressure eventually leading todeterioration or damage of the shower hose.

The internal pressure of the shower hose when water is stopped by thehand-operated valve changes variously depending on the closure speedthereof. The value of internal pressure in the shower hose when water isstopped by the hand-held operation on the shower head end is basicallydetermined by a specification of the pressure adjusting valve. However,when the hand-operated valve is closed all at once, the pressureadjusting valve is closed with a high internal pressure in the showerhose because water hammer also occurs, and such high internal pressureis subsequently maintained after valve closure. Thus, load on the showerhose is increased thereby inducing deterioration or damage.

In a type of shower apparatus in which the pressure adjusting valve isimproved by reducing its size by combination of the piston and cylinder,hydraulic pressure is sometimes applied in a direction of opening thevalve due to a clearance between the piston and the cylinder. Thus, ifwater is stopped by hand-held operation of a valve on the shower headwhen the supply water pressure is high, a force keeping the valve of thepressure adjusting valve closed is weakened, and unless the internalpressure in the shower hose is high, it is not possible to stop thesupply of water by means of the pressure adjusting valve.

Furthermore, because a function of the pressure adjusting valve is tohold the secondary pressure at a constant value by adjusting an amountof flow to the shower head, the higher the supply pressure on the watersupply side, the more the flow route of the pressure adjusting valve isthrottled. Thus, if the supply pressure is high, the velocity of flowwhen water passes through a throttled flow route is increased. If thepressure adjusting valve is closed while this condition is present, asignificant water hammer occurs.

Even if the pressure responding valve and the pressure adjusting valveor the like are equipped to prevent occurrence of water hammer asdescribed above, if the feed of water is stopped by the hand-heldoperation of the valve on the shower head side, a temporary rise of theinternal pressure in respective parts including the shower hose isunavoidable.

An object of the present invention is to suppress an increase inpressure due to water hammer which may occur particularly when the feedof water is stopped, in a shower apparatus in which discharge of waterand stopping of water is carried out on the shower head side, andthereby reduce pressure applied to respective parts including the showerhose, thereby maintaining continued viability of the parts.

SUMMARY OF THE INVENTION

The present invention comprises a pressure adjusting means for adjustingthe pressure of supply fluid, and a flow amount adjusting means foradjusting an amount of flow of the supply fluid depending on the degreeof opening thereof to a discharge end of the shower head, the pressureadjusting means and the flow amount adjusting means being disposedsuccessively from the upstream end of a flow route between a shower sideflow route provided in a water plug and a shower head or a discharge endof the shower head. The present invention further comprises a pressurecushioning means for cushioning an increase in the internal pressure ofthe flow route which occurs when the flow route is closed by the flowamount adjusting means, provided as a flow route system capable ofcushioning an increase in the internal pressure of the flow route whenthe flow amount adjusting means is operated.

According to the above described construction, it is possible to disposea pressure cushioning means for cushioning an increase in the internalpressure of the flow route which may occur from a water plug when thepressure adjusting means closes the flow route. Further it is possibleto incorporate an opening valve as a flow amount adjusting means in theshower head and which further contains an operating portion.

By including such pressure cushioning means, the increase in theinternal pressure of the hose when the valve is closed on the showerhead end is absorbed and the pressure cushioning means provided in theshower head or a flow route up to the pressure adjusting valvesuppresses an increase in the internal pressure, thereby reducing theload from changes in pressure acting upon the hose.

In a type of shower apparatus in which the pressure cushioning meanscomprises a control valve body in a pressure adjusting valve and apressure chamber, an increase in pressure which occurs when an openingvalve such as that in a shower head is closed is absorbed by expansionof the volume, thereby preventing an increase in the internal pressureof the hose.

Because the control valve body which serves as the pressure adjustingmeans can be moved in a direction such that the internal volume of thepressure chamber is increased even after the flow route from a fluidsupply source is shut down when the internal pressure of the hose isincreased, an increase of the internal pressure which cannot be absorbedby the cushioning means on the shower head side is restricted andabsorbed by the pressure adjusting valve.

In a type of shower apparatus in which a variable volume structure isutilized as a pressure cushioning means, by making a small hole in abore open to a throat in an orifice on an internal flow route, apressure transmitted to a variable volume body or the like can bereduced, thereby simplifying constructional considerations relating tostrength and structure.

In a type of shower apparatus in which a leak mechanism is utilized as apressure cushioning means, only the opening valve mechanism may be aspecial device, so that the opening valve and the pressure cushioningmeans can be combined. Further, in a valve switching mechanism type inwhich the opening valve is switched to the discharge side and waterstopping side, if the leak mechanism is disposed in the flow route ofthe water stopping side, it is possible to release an increase inpressure which occurs at the time water flow is stopped or when theopening valve is closed through the leak mechanism.

In a type of shower apparatus in which a mild stopping mechanism isutilized as a pressure cushioning means, an occurrence of water hammeris eliminated because rapid closing of the opening valve never occurs,thereby making it possible to maintain a further stabilized maintenanceof the internal pressure.

Further, in a type of shower apparatus in which the opening valve isopened or closed by thrust lock mechanism, shower operation can beimplemented only by pressing the operating portion once by hand. If theoperating portion is pressed again, it is possible to stop operation ofthe shower.

The above, and other objects, features and advantages of the presentinvention will become apparent from the following description read inconjunction with the accompanying drawings, in which like referencenumerals designate the same elements.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a schematic view showing a system in which a shower apparatusof the present invention is connected to a hot water/cold water mixingplug.

FIG. 2 is a transverse sectional view of major parts for absorbingpressure by means of a pressure responding valve disposed between amixing water exit and the hose of a hot water/cold water mixing plug.

FIG. 3(a) shows an example of a stroke action of a control body as inFIG. 2 in which water is stopped by a sliding portion of the controlvalve body and a packing on the valve hole side.

FIG. 3(b) shows an example of a stroke action of a control body as inFIG. 2 in which water is stopped by packing disposed in a circumferenceof the control valve body fittable to an internal circumference of thevalve hole.

FIGS. 4(a) and 4(b) show an example in which a cone is provided on thefront end of the control valve body, and provides schematic views forexplaining a phenomenon where the speed of closing the valve isincreased when water hammer occurs on a hose side.

FIGS. 5(a) and 5(b) are schematic views showing an example in which thespeed of closing the valve is decreased by using a different shape ofcontrol valve body from that shown in 4(a) and 4(b).

FIG. 6 is a longitudinal sectional view of major parts illustrating howa U-shaped packing is provided in an external circumference of thecontrol valve body, and how the control valve body is pushed in adirection for opening the valve by a primary side pressure.

FIG. 7 is a longitudinal sectional view of major parts showing a case inwhich, by balancing the operating force on the packing by primary sidepressure instead of the control valve body shown in FIG. 6, closing ofthe valve with stabilized operation of the control valve body isrealized.

FIG. 8 is a longitudinal sectional view of major parts showing anembodiment in which, by providing an internal circumference of a guidefor guiding the control valve body with a U-shaped packing, the load onthe control valve body in the direction for opening of the valve by theprimary side pressure is eliminated.

FIG. 9 is a longitudinal sectional view of major parts of a pressureadjusting valve structured so as to adjust the initial load of a springfor urging the control valve in the direction for opening the valve.

FIG. 10 is a perspective view of disassembled parts for adjusting theinitial load of the spring shown in FIG. 9.

FIG. 11 is a longitudinal sectional view of an embodiment in which apressure absorbing mechanism using a piston is employed upstream of theopening valve provided in the main body of the shower head.

FIG. 12 is a disassembly perspective view of a sleeve, a guide and aspindle in the pressure absorbing mechanism shown in FIG. 11.

FIG. 13(a) is a detailed front view of a guide ring.

FIG. 13(b) is a detailed longitudinal sectional view taken along thelines A--A in FIG. 13(a).

FIG. 13(c) is an expansion view of slits made in a circumferential wallof a guide ring.

FIG. 14 is a longitudinal sectional view showing an example in which atube is provided in the pressure absorbing mechanism instead of apiston.

FIG. 15 is a longitudinal sectional view of an example containing apressure absorbing mechanism for releasing a pressure in the upstream tothe downstream after a valve closing operation is terminated.

FIG. 16 is a longitudinal sectional view showing details of the openingvalve shown in FIG. 15.

FIG. 17 is a perspective view showing disassembled parts of the openingvalve shown in FIG. 15.

FIGS. 18(a) 18(b) and 18(c) are longitudinal sectional view of majorparts showing another example of the opening valve which allows water toescape when pressure rises.

FIG. 19 is a longitudinal sectional view of major parts showing anexample which is provided with a valve for water release at a sprayplate of the shower head.

FIG. 20 is a longitudinal sectional view of an example of a mildstopping mechanism comprising a piston provided on a spindle of theopening valve and damper bore provided in the main body of the showerhead.

FIG. 21 is a longitudinal sectional view of an example in which mildclosing of the opening valve is made possible by the shape of thepacking of the opening valve.

FIG. 22(a) is a detailed perspective view taken from the front end of apacking shown in FIG. 2.

FIG. 22(b) is a diagram of the packing shown in FIG. 21 showing apositional relation of the packing with respect to the valve hole in thevalve seat.

FIG. 23 is a longitudinal sectional view of major parts showing anexample in which a block and a tube are provided as pressure cushioningmeans in the upstream of the pressure adjusting valve shown in FIG. 9.

DETAILED DESCRIPTION OF THE INVENTION

FIG. 1 is a drawing showing a scheme of a general example of a showerapparatus.

Referring to the figures, and in particular FIG. 1, a general example ofa shower apparatus is depicted therein. In the shower apparatus, ashower head 3 is connected to a hot water/cold water mixing plug 1, forexample, fixed to a wall of a bathroom, through a hose 2. The hotwater/cold water mixing plug 1 receives supplies of hot water and coldwater, and can change a flow route to a discharge pipe 1a or a hose 2 ina conventional manner.

The shower head 3 is connected to the hose 2 at its proximal end and hasa spray plate 3a at its flow route end. According to the presentinvention, an operation portion 3b for supply and stopping of mixingwater to the spray plate 3a is provided. This operation portion 3b issuitably structured to only carry out discharge and stopping of water byopening or closing the flow route or to be capable of adjusting the flowof water by changing the degree of opening of its valve.

Between a mixing water exit 1b of the hot water/cold water mixing plug 1and the hose 2, a pressure adjusting valve 21 is provided which absorbsa rise in internal pressure when the valve is closed by the operationportion 3b of the shower head 3. As shown in the transverse sectionalview of FIG. 2, this pressure adjusting valve 21 contains a partitionwall 21a which partitions a side of the mixing water exit 1b from aportion communicating with the hose 2. At a portion which is around avalve hole 22 made in the partition wall 21a and which faces a chamberon a side of the mixing water exit 1b, a packing 23 is provided.

At a flow route on a side of the mixing water exit 1b relative to thepartition wall 21a, a pressure chamber 24 is provided which is disposedon the same axis as the valve hole 22. In this pressure chamber 24, acontrol valve body 25, for absorbing a rise in pressure when the valveis closed and water flow is stopped, is incorporated to face thepartition wall 21a so as to be able to advance or retract. This controlvalve body 25 can slide along a guide 24a protruding from the pressurechamber 24 toward the partition wall 21a in a water-tight condition, andis also slidable in water tight conditions with respect to an internalwall of the pressure chamber 24, so that it is urged in a directionleaving the partition wall 21a by a spring 26. The control valve body 25contains a communication route 25a provided from a front end thereoffacing a flow route on the valve hole 22 side to a rear end thereof inan axial direction and a space 27 formed between the pressure chamber 24and the sliding portion of the control valve body 25 is made tocommunicate with a flow route from the mixing water exit 1b to the hose2 by means of this communicating route 25a.

At a front end of the control valve body 25 a cone 25b is formed havinga shape which gradually narrows toward an end thereof as shown in FIG.39(a). At a rear portion thereof from its proximal end is a slidingportion 25c having the same diameter, allowing sliding within the guide24a. The packing 23 provided around the valve hole 22 has an internaldiameter which can stop water with the sealing circumference of thesliding portion 25c when it is inserted into the valve hole 22.

If the flow route is opened by the operation portion 3b of the showerhead 3, mixing water is supplied from the hot water/cold water mixingplug 1 and flows through the valve hole 22 in the pressure adjustingvalve 21, and into the hose 2. Depending on the throttling of the valvehole 22, the velocity of water flow back and forth therethroughincreases so that the pressure around the front end of the cone 25b ofthe control valve body 25 drops. Thus, internal pressure in the space 27communicating therewith through the communication route 25a also drops,so that the control valve body 25 is held at the position shown in FIG.2 by the force of the spring 26, and then the supply of mixing waterthrough the valve hole 22 to the hose 2 is continued.

If the flow route is closed by means of the operation portion 3b of theshower head 3, the internal pressure in the flow route of the hose 2increases. At such time, the stream of mixing water is also stopped andthus the pressure around the valve hole 22 becomes equal to the internalpressure of the hose 2. The increase of pressure after the valve isclosed is transmitted to the space 27 through the communication route25a in the control valve body 25. Thus the internal pressure in thisspace increases so as to contract the spring 26. Consequently thecontrol valve body 25 moves toward the valve hole 22 and, as shown inFIG. 3(a), the sliding portion 25c engages the packing 23 therebyshutting down the flow route.

This action of the control valve body 25 not only shuts the flow routeto the hose 2 but also increases an internal volume of the space 27formed between the control valve body 25 and the pressure chamber 24.Because this space 27 communicates with the flow route on a side of thehose 2 even after the flow route is shut down, the increase in theinternal pressure can be absorbed by an increase in volume of the space27. According to this embodiment, the pressure adjusting valve 21 is sostructured to contain a pressure adjusting function by respectiveactions of the control valve body and pressure cushioning function, forcoping with a time when the internal pressure in the flow route isincreased. The pressure adjusting means and pressure cushioning meansare integrally constructed.

Although the valve hole 22 is completely shut in a state shown in FIG.3(a), the control valve body 25 can be moved further rightward from theindicated state. The control valve body 25 moves freely corresponding topropagation of pressure to the space 27 to cope with an increase inpressure or pulsation just after the valve of the shower head side isclosed, in order to absorb that increase in pressure by changing thevolume of the space 27.

Even if the mixing water supplied from the mixing water exit 1b is ofhigh pressure, it flows into the space 27 through the communicationroute 25a in the control valve body 25 so that the control valve body 25is moved to the side of the valve hole 22, resisting the force of thespring 26. If the control valve body 25 is moved so as to enter thevalve hole 22, the flow amount is throttled, so that hydraulic pressurein the communication route 25a and the space 27 drops and the controlvalve body 25 is thereby stabilized at such a position that thehydraulic pressure is balanced with the spring 26. Thus, even if highpressure mixing water is supplied, stabilized low pressure mixing wateris supplied to the hose 2 by the pressure adjusting valve 21.

When high pressure mixing water is supplied, when an opening valve 5 ofthe shower head 3 is closed, the pressure in the space 27 increases inthe above example, so that the control valve body 25 is moved from theposition in which a balance with the spring 26 is obtained toward thevalve hole 22 thereby shutting the valve hole 22. Thus the hose 2 isseparated from the high pressure mixing water, and thus only a slightlyhigher pressure than the constant pressure when the valve is opened isapplied, thereby preventing the hose from deterioration or damage.

The spring 26 should have a force such that hydraulic pressure at theside of the hose 2 is less than 1 kg/cm2 when water is made to pass, anda spring constant and number of windings of coils such that thehydraulic pressure is less than 2 kg/cm2 when water feeding is stopped.

An action for stopping water supply and absorbing pressure by thecontrol valve body 25 is enabled by a relation between the slidingportion 25c of the control valve body 25 and the valve hole 22 as shownin FIG. 3(b). In this example, the length in axial direction of thevalve hole 22 is quite long and the packing 25d comprising an O-ring orthe like is suitably structured to enter the valve hole 22 as showntherein when the internal pressure in the flow route is increased,thereby stopping water flow. Further, because such an action of changingthe volume of the space 27 is achieved by moving the control valve body25 in a stroke in which the packing 25d is located within the valve hole22, it is possible to carry out absorption of pressure according to theinternal pressure in the flow route.

As described above, after the control valve body 25 shuts down the flowroute as well, the space 27 is made to communicate with the hose 2through the communication route 25a, and the control valve body 25itself can move freely in its stroke direction. Thus, even if theincrease in pressure continues after the valve of the shower head isclosed, this increase of pressure is absorbed so as to reduce thepressure load on the hose 2.

FIGS. 4(a), 4(b), 5(a) and 5(b) are schematic views for explainingwhether reduction of pressure load by water hammer applied to the sideof the hot water/cold water mixing plug is enabled, depending on thedifference in the shape of the front end of the control valve body 25.

Referring to FIG. 4, the packing 23 provided around the valve hole 22 isdifferent from the packing shown in FIG. 3 in that the former isdisposed in an annular shape for receiving only the front portion of thecontrol valve body 25, and stops water flow by an engagement of thecontrol valve body 25 with the packing 25. The front portion of thecontrol valve body 25 is formed in a conical shape 25e and annularsettling ring 25f is disposed at a proximal portion of this cone 25e soas to protrude therefrom. When the control valve body 25 is moved towater flow stopping position, this settling ring 25f is structured so asto strike an end face of the packing 23.

The control valve body 25 having such a cone 25e is also maintained at aposition in which the secondary side pressure is balanced with thespring 26 when water is being fed as in the previous example. Forexample, when the primary side pressure is normal and the position inwhich the cone 25e is maintained is as shown in FIG. 4(a), when theprimary side pressure is high, a velocity of flow around a throttleportion between the circumference of the cone 25e and the valve hole 22increases so that pressure applied to this portion is decreased and, atthe same time, the internal pressure of the space 27 rises. Thus, thecontrol valve body 25 is moved to a position shown in FIG. 4(b) and isbalanced there such that the distance between the settling ring 25f andthe packing 23 is reduced.

If water flow is stopped by the operation portion 3b of the shower head3, the pressure in the space 27 increases so that the control valve body25 is moved further rightward and the settling ring 25f is fit to thepacking 23 so as to close this valve. At this time, because the distancebetween the settling ring 25f and the packing 23 is reduced, the openingspeed of the valve is increased so that consequently a rise in pressuredue to water hammer on the side of the hot water/cold water mixing plug1 is increased.

Alternatively, although in the control valve body shown in FIGS. 5(a)and 5(b) the shape of the settling ring 25f and the like is the same asshown in FIG. 4, the cone 25g is provided only on its front end portionand the axial length thereof is less than the cone 25g shown in FIGS.4(a) and 4(b). Further, a portion which is located at the proximal endand protruding slightly from a portion surrounded by the settling ring25f so as to connect to the cone 25g is a straight portion 25h having anequal diameter. At a time of normal water feeding, as in the case shownin FIGS. 4(a) and (b), the control valve body 25 is balanced at aposition shown in FIG. 5(a).

By providing the cone 25g only on the front end of the portionprotruding from the settling ring 25f, when the control valve body 25 islocated at a position shown in FIG. 5(b) when the primary side pressureis increased, the control valve body 25 is balanced at a positionfarther apart from the packing 23 as compared to the example shown inFIGS. 4(a) and 4(b). This is because the degree of throttle by the cone25g with respect to the valve hole 22 is larger than the example shownin FIG. 4. Thus, the distance between the packing 23 and the settlingring 25f is greater, so that the closing speed of the valve of thecontrol valve body 25 when water hammer occurs due to stopping of waterflow on the shower head side is lowered as compared to the example shownin FIGS. 4(a) and (b), thereby cushioning a rise of internal pressure inthe hot water/cold water mixing plug 1.

FIGS. 6, 7 are drawings for explaining whether reduction of the internalpressure in the hose 2 when water feeding on the shower head side 3 isstopped is enabled, the depicted embodiment being distinguished from apreceding embodiment by a difference in the sealing structure betweenthe control valve body 25 and the guide 21b for guiding this controlvalve body 25.

Referring to FIG. 6, a control valve body 25, having substantially thesame external diameter as the internal diameter of a cylindrical guide21b formed on the same axis as the valve hole 22, is incorporated in theinterior of the pressure adjusting valve 21 so as to be slidablethereon, and packing 25j, having a U-shaped cross section, is embeddedin an annular groove 25i formed in the external circumferential face ofthe control valve body 25. The packing 25j is incorporated so that theface directed to the front end of the control valve body 25 is in theform of a concave cross section. Thus, the primary side pressure acts ina manner pressing the packing 25j to the left as shown by theenlargement in FIG. 6 through a clearance between the control valve body25 and the guide 21b.

In accordance with this embodiment, when water feeding in the showerhead 3 is stopped, the internal pressure in the hose 2 is transmitted tothe space 27 in a manner tending to urge the control valve body 25 tothe right in order to close the valve. However, because the primary sidepressure acts on the packing 25j and a pressure loading area thereof islarger than an end face of the annular groove 25i, the control valvebody 25 receives a load pushing to the left, i.e. a direction that thevalve is opened, by the primary side pressure. Thus, if the primary sidepressure is high, the force of the control valve body 25 in thedirection of valve opening increases so that the force on the settlingring 25f pushing against the packing 23 lessens.

If the force of the control valve body 25 to contact the packing 23lessens, there is a possibility that the control valve body 25 maytemporarily leave the packing 23 when water hammer occurs, so that theprimary side pressure is transmitted into the hose 2. Consequently, theinternal pressure of the hose 2 increases rapidly.

Alternatively, the control valve body 25 shown in FIG. 7 has a smallerdiameter portion 25k which extends from the annular groove 25i to nearthe settling ring 25f and has an external circumferential face smallerthan the previous example. At an end portion of this smaller diameterportion 25k a pressure receiving face 25m is formed directed opposite tothe settling face of the settling ring 25f. An external diameter of theportion forming this pressure receiving surface 25m is structured to beslightly smaller than the internal diameter of the guide 21b and by thisdevice, it is possible to make total acting area of the end face of theannular groove 25i and the pressure receiving surface 25m equal to theacting area in which the primary side pressure applied to the packing25j acts. Thus, the primary side pressure which pushes the packing 25jto the left is balanced with the end face of the annular groove 25i andthe primary side pressure pushing the pressure receiving surface 25m. Asa result, if the primary side pressure is high, it is possible tomaintain a state in which the control valve body 25 is pushed securelyagainst the packing 23.

By forming the control valve body 25 in such a shape that the primaryside pressure to the control valve body 25 is attenuated in a directionof opening the valve, it is possible to keep the control valve body 25closed even when the primary side pressure is high, thereby making itpossible to reduce a rise in the internal pressure in the hose 2.

FIG. 8 is a longitudinal sectional view showing an example in which thepacking 21d having a U-shaped cross section is embedded in the annulargroove 21c provided in the internal circumference of the guide 21b.

In the examples shown in FIGS. 6, 7, the packing 25i is provided in theannular groove 25j formed in the control valve body 25. Thus, if theprimary side pressure is high, the control valve body 25 is pushed inthe direction of opening the valve by a load received by this packing25i.

In the example shown in FIG. 8, the packing 21d is contained in theguide 21b side and the control valve body 25 is structured such that theexternal circumference thereof is made to slide relative to the packing21d. Even if the primary side pressure is so high that the load acts onthe packing 21d through the clearance between the control valve body 25and the guide 21b, the control valve body 25 only acts as a pressurereceiving face in which the settling ring 25f located at the front endprovides the maximum diameter. The load acting on the packing 21d onlyincreases sliding resistance of the control valve body 25 relative tothe circumference thereof and produces no action for moving the controlvalve body 25 in the direction of opening the valve. Thus, even if theprimary side pressure is high, it is possible to reduce a rise inpressure in the hose 2 and the hot water/cold water mixing plug 1 due towater hammer produced when water feeding is stopped in the shower head3.

FIG. 9 is a longitudinal sectional view of major components showing afurther practical embodiment of the pressure adjusting valve 21 shown inFIG. 2. The same components as previously shown are indicated by thesame reference numerals and a detailed description thereof is omitted.

The control valve body 25 is disposed by the guide 21b so that it isretractable relative to the valve hole 22. An initial load of the spring26 for urging the control valve body 25 in the direction of opening thevalve can be adjusted.

For adjustment of the initial load of this spring 26, a moving element28 is incorporated in the pressure chamber 24 and, at the same time, anoperation element 29 which can be rotated from outside is provided.

FIG. 10 is a disassembly perspective view of the guide 21b, the movingelement 28 and the operation element 29. At two positions on theexternal circumference of the guide 21b into which the control valvebody 25 is to be inserted, slide grooves 21b-1 are formed in an axialdirection. The moving element 28 has a sleeve 28a into which the guide21b is slidably inserted from outside. By inserting protruding rails 28bprovided on the internal circumference of this sleeve 28a into theguides 21b-1, the moving element 28 can be moved only in the axialdirection without being rotated around the guide 21b and is providedwith a protrusion 28c on the external circumference.

The operation element 29 is rotatably incorporated on the same axis asthe pressure chamber 24 and a motion thereof in the axial direction isblocked by a plug 21e connected to an end face of the pressure adjustingvalve 21. An internal circumference thereof serves as a sliding surfacefor the control valve body 25 in the axial direction and a slidingsurface for the moving element in the rotation direction. A tool hookingportion 29a is provided in a portion protruding from the plug 21e, and aslit 29b is made in a portion of the operation element in which themoving element 28 is inserted, the slit being disposed from an endportion thereof toward the circumferential surface.

The slit 29b has an opening width allowing the protrusion 28c of themoving element 28 to be inserted therein and is developed in thecircumferential direction having torsion with respect to the axis of theoperation element 29. Thus, if the operation portion 29 is rotatedclockwise as viewed in FIG. 10, the moving element 28 is moved to theleft as viewed in the same figure due to the relative motion of theprotrusion 28c within the slit 29b. If the operation element 29 isrotated counterclockwise, the moving element is moved to the right.

By providing the aforementioned configurations of moving element 28 andthe operation element 29, the moving element 28 can be moved to theright and the left depending on the direction of the rotation of theoperation element 29. The spring 26 is structured so that an end thereofstrikes the proximal end of the control valve body and the other endthereof strikes the moving element 28. Thus, if the moving element 28 ismoved to the left, compression of the spring 26 is enhanced. If themoving element 28 is moved to the right, the load on the spring 26 isreduced. Thus, even after the spring 26 is incorporated in the pressureadjusting valve 21, the initial load to the spring 26 can be changed byturning the operation element 29.

Because the initial load of the spring 26 can be easily set and changed,even if supplied hydraulic pressure changes, the restoration force ofthe spring 26 can be adjusted so as to reduce the internal pressure ofthe hose 2. As a result, it is possible to reduce a rise in pressurewhich occurs in the hose 2 and the hot water/cold water mixing plug whenwater feeding is stopped on the water head 3 side. Even if an erroroccurs in spring loading during production of the spring 26, byadjusting the initial load of the spring 26 it is possible to maintainthe function of the pressure adjusting valve 21 notwithstanding suchproduction error.

As described previously, when the primary side pressure is particularlyhigh, the closing speed of the valve of the control valve body 25 whichis induced when water feeding is stopped in the shower head 3 isincreased so that water hammer occurs due to closing of the flow routeby the control valve body 25. To reduce this water hammer, it iseffective to decrease the internal diameter of the communication route25a. For example, the internal diameter should preferably be about 0.3mm-1.5 mm.

That is, when the control valve body 25 is moved toward the packing 23or toward a position in which the valve is closed, the volume of thespace 27 occupying the rear portion of the control valve body 25 isgradually increased. By the motion of this control valve body 25, astream of water directed to the space 27 from the front end of thecontrol valve body 25 is induced, accompanied by an increase in thevolume of the space 27. Thus, if the flow of water directed to the space27 is throttled by decreasing the internal diameter of the communicationroute 25a, the speed of the control valve body 25 can be decreased byutilizing resistance of water. Thus, it is possible to reduce waterhammer which occurs when the control valve body 25 closes the valve. Onthe other hand, if the internal diameter of the communication route 25ais brought below 0.3 mm, the moving speed of the control valve body 25is decreased. Even if the operation portion 3b of the shower head 3 isoperated to open same, the opening speed of the control valve body 25 isdecreased so that the spray of water from the shower head 3 is delayed.

When the control valve body 25 is closed, except in the examples shownin FIG. 3, the settling ring 25f strikes the surface of the packing 23along the same axis. In this type of valve-closing, by decreasing thehardness of the packing 23, it is possible to move the control valvebody 25 further, as in the example indicated in FIG. 3, so that itimbeds more securely in the packing 23, even after the valve is alreadyclosed.

The hardness of ordinary packing for use in valves used to stop the flowof water is about 90 degrees. Because this packing is always in a statein which the valve is closed and compressed and sometimes tightenedexcessively by manual operation, a packing produced according tospecifications which resist deformation is utilized. Thus, it ispreferable that the hardness of the packing 23 under respectiveembodiments is 40-70 degrees. If such a hardness is ensured, after thevalve is closed, as described above, the control valve body 25 can bemoved a little, thereby contributing to reduction of water hammer andfurther ensuring a high degree of sealing performance. If the hardnessof the packing is less than 40 degrees, the strength of the packing isdecreased so that external deformation is likely to be produced.

FIG. 11 is a longitudinal sectional view of the shower head according tothe present invention.

Like the shower head shown in FIG. 1, the hose 2 is connected to aproximal end of the main body 4 of the shower head and a spray plate 4ahaving a number of small holes is attached to its front end. An openingvalve 5 is provided to open and close an inside flow route at a middleportion of the main body 4.

In the opening valve 5, a guide ring 5b is mounted on a sleeve 5ascrewed to the main body 4 so that it is rotatable on the same axis asthe sleeve 5a and, further, a spindle 5c is incorporated in this guidering 5b so that it is rotatable on the same axis. The opening valve 5 isstructured so that the packing 5d provided the same axis. The openingvalve 5 is structured so that the packing 5d provided at the front endof the spindle 5c is separable as a valve disc from an annular

FIG. 12 is a disassembly perspective view of the sleeve 5a, the guidering 5b and the spindle 5c and FIG. 13(a), (b) and (c) are detail of theguide ring 5b.

The sleeve 5a is a hollow object having different diameters and, in aninternal circumference of the lower half of the object, holding grooves5e are radial direction and in the axial direction. The spindle 5c hastwo protrusions 5f radial direction and in the axial direction. Thespindle 5c has two protrusions 5f which are incorporated slidably in theholding grooves 5e in the sleeve 5a. rotation operations and isincorporated in the sleeve 5a through a packing 5h. The guide ring 5bhas a hollow interior in which the spindle 5c is inserted. Two guidering 5b has a hollow interior in which the spindle 5c is inserted. Twocircumferential direction as shown in FIG. 12 so that the protrusions 5fof the spindle 5c can be inserted into the slits 5i. As shown in theexpansion drawing of FIG. 13(c), the slits 5i are formed obliquelyrelative to the axis of the guide ring 5b.

With respect to the sleeve 5a fixed to the main body 4, the guide ring5b is freely rotatable around an axis thereof. By inserting theprotrusions 5f of the spindle 5c, protruding through the slits 5i ofthis guide ring 5b, into the holding grooves 5e of the sleeve 5a, thespindle 5c cannot be rotated around the axis thereof as it is held bythe protrusions 5f and the holding grooves 5e and can only thereof as itis held by the protrusions 5f and the holding grooves 5e and can onlyrotated, the protrusions 5f are moved relatively through the obliqueslits 5i so that a position of the spindle 5c is changed along the axialdirection. a position of the spindle 5c is changed along the axialdirection.

In this opening valve 5, the spindle 5c is set from the state in whichthe packing 5d is settled on the valve seat 4b by turning the knob 5gonly a half turn, because of the protrusion 5f and the slit 5i. Turningthe knob 5g in the opposite direction opens the valve from the waterstopping position.

To prevent a rise of internal pressure due to water hammer which occurswhen the opening valve is opened, a pressure cushioning means isprovided just upstream of the opening valve 5. This pressure cushioningmeans comprises a upstream of the opening valve 5. This pressurecushioning means comprises a therein.

In the block 6, an orifice 6a is formed for providing communicationbetween the bottom end of the main body 4 and the valve seat 4b side,and a bore 6c for communicating with a throat portion of the orifice 6athrough a small hole 6b. At an opening end of the bore 6c, a plug 6dhaving a small hole 6e is detachably mounted. A piston 7 is incorporatedin the bore 6c through packings 7a in water-tight condition, urgedtoward the orifice 6a by a spring 7b.

With the above described structure, if the knob 5g is turned to closethe opening valve 5 after a shower, the spindle 5c is moved rapidlytoward the valve seat 4b as described previously, so that the packing 5dis settled on the valve seat 4b to shut down the water flow route.Although a rise in the internal pressure in the flow route is increaseddownstream of the opening valve 5 because of the shut-down of the flowroute at this time, pressure is transmitted to the bore 6c communicatingwith the internal flow route through the small hole 6b. Then, the piston7 receives this pressure so as to contract the spring 7b, and the pistonis then moved to the left as shown in FIG. 11 so that the internalvolume of the bore 6c residing on the side of the small hole 6b isincreased.

As described above, an increase in pressure in the internal flow routewhich may occur when the opening valve 5 is closed is absorbed by anincrease in the volume of the bore 6c communicating with the internalflow route downstream of the opening valve 5, thereby making it possibleto suppress a rise in internal pressure which may occur just after thevalve is closed. Thus, the load from internal pressure to the hose 2 isreduced so as to prevent deterioration of the pressure resistantproperties and sealing performance of a joint.

The small hole 6b through which the bore 6c communicates with theinternal flow route is opened to the throat portion in the orifice 6a.Attendant a rise in internal pressure, the increase in pressure in thisthroat portion is smaller when compared to a portion which has a largeflow route area. Thus, transmission of pressure to the bore 6c isreduced and the spring 7b need only have an elasticity sufficient forallowing the piston 7 to move depending on the rise in the pressure.Thus, pressure resistance of the spring 7b can be minimized and the sizeof the spring 7b can be reduced, thus enabling a reduction in the sizeof the block 6.

FIG. 14 is an example in which a variable volume object whose internalvolume can be varied is incorporated in the bore 6c instead of thepiston 7 in the example in FIG. 11.

The example of such variable volume object shown in FIG. 14 is a tube 8which is held by a plug 8a in the bore 6c shutting the bore 6c from theoutside. In this case, when the tube 8 is employed, because oftransmission of pressure into the bore 6c caused by a rise of internalpressure in the flow route after the opening valve 5 is closed, the tube8 is contracted and deformed so that a volume communicating with theinternal flow route side is expanded. Thus, like the example indicatedin FIG. 11, it is possible to eliminate problems attendant theoccurrence of water hammer and a steep rise of the internal pressurejust after the valve is closed.

Alternatively, if a foamed substance which can be contracted anddeformed due to an external pressure is incorporated instead of the tube8, the same operation and effect can be obtained.

FIG. 15 is an example employing a mechanism for releasing a pressurethrough a spray plate 4a to the atmosphere by temporarily setting thevalve in the opening state by an increase in the internal pressure ofthe flow route in the upstream just after the valve is closed.

Like the examples shown in FIGS. 11 and 14, the opening valve 9 isprovided at a position corresponding to the valve seat 4b formed in themain body 4.

FIG. 16 is a longitudinal sectional view showing a detail of the openingvalve 9 and FIG. 17 is a perspective view of disassembled componentsthereof. A guide ring 9b is incorporated into a sleeve 9a screwed to themain body 4 such that it is freely rotatable on the same axis. A movingelement 9c is inserted into this guide ring 9b and a spindle 9d having apacking 9e at one end is movably incorporated in the moving element 9c.

A composition of the sleeve 9a, the guide ring 9b and the moving element9c is almost the same as that shown in FIG. 12. Two holding grooves 9fare made in an internal circumference of the sleeve 9a and two obliqueslit 9g are formed in an circumferential wall of the guide ring 9b. Twoprotrusions 9h which penetrate through these slits 9g and enter into theholding grooves 9f are formed so as to protrude from an externalcircumference of the moving element 9c in the radial direction. Withthis structure, if a knob 9b-1 provided on a top end of the guide ring9b is rotated, the moving element 9c is not rotated around its axis butmoved vertically as viewed in FIG. 9 because the protrusions 9hpenetrating through the slit 9g are inserted into the holding grooves 9fof the sleeve 9a. As in the previous example, because of the inclinationof the slit 9g in the guide ring 9b, the moving element 9c is movedrapidly merely by turning the knob 9b-1 a small amount.

The spindle 9d inserted into the moving element 9c is restricted frombeing moved downward or in the direction of valve closure by means of aring 9d-1 engaging an external side face of the moving element 9c, and acompression coil spring 9i is incorporated between a flange 9d-2 onwhich a packing 9e is mounted at a top end portion of the guide ring 9b.Consequently, referring to FIG. 16, if a force pushing the packing 9eupward is applied, the spindle 9d contracts the spring 9i so that itmoves upward with respect to the guide ring 9b, that is, in the openingdirection of the valve.

If the opening valve 9, now in the state in which the valve is closed asshown in FIG. 15, is closed by means of the knob 9b-1, the movingelement 9c and the spindle 9d are integrally moved toward the valve seat4b so that the packing 9e is settled on the valve seat 4b to close thevalve. If water hammer or a sudden increase in pressure occurs in theupstream of the opening valve 5 at this time, this pressure is receivedby the packing 9e. Thus, if a spring constant of the coil spring 9i isset to an appropriate level, it is possible to move only the spindle 9,now in the state in which the valve is closed as shown in FIG. 15, isclosed by means of the knob 9b-1, the moving element 9c and the spindle9d are integrally moved toward the valve seat 4b so that the packing 9eis settled on the valve seat 4b to close the valve. If water hammer or asudden increase in pressure occurs in the upstream of the opening valve5 at this time, this pressure is received by the packing 9e. Thus, if aspring constant of the coil spring 9i is set to an appropriate level, itis possible to move only the spindle 9d in a direction of beingseparated from the valve seat 4b by means of contraction of the coilspring 9i because of the increase in pressure. Thus, if the increase inpressure occurs upstream of the opening valve 5, this is not included inthe flow route but can be released via the small holes in the sprayplate 4a downstream.

By structuring the spindle 9d which can be set at the valve openingposition and valve closing position such that it is movable in theopening direction of the valve by receiving a pressure from upstreamwhen the valve is closed, it is possible to reduce the pressure load onthe hose 2 due to water hammer or sudden increase in pressure.

FIGS. 18(a), (b) and (c) are a longitudinal sectional view of majorparts of other structures for allowing water to escape to the waterspray side when an increase in pressure occurs upstream after theopening valve is closed as in FIG. 15.

The main body 4 of the shower head incorporates an opening valve 31 atthe same position as in FIG. 15. The opening valve 31 can open and closea flow route connected between a valve hole 4g surrounded by a valveseat 4f provided on a partition wall 4e and a communicating hole 4hcommunicating with a side of the spray plate formed downstream, and isheld by a bushing 31a fixed to the main body 4.

An operation button 32 is assembled into the bushing 31a in water-tightcondition so that it can be moved in the direction of the valve seat 4f.This button is urged in the direction away from the main body 4 by acoil spring 33 disposed between the button 32 and the partition wall 4e.In the button 32, a valve body 34 capable of settling on the valve seat4f is contained to communicate with the bushing 31a by means of a heartshaped cam 35 of conventional technology, and the valve body 34 is urgedin the direction of the valve seat 4f by a coil spring 36. By acombination of the heart shaped cam 35 and the coil spring 36, the valvebody 34 can be contained so as to communicate with the bushing 31a bymeans of a thrust lock mechanism of conventional technology applied, forexample, to ball-point pens and the like.

With this thrust lock mechanism, if the button 32 is pressed in thestate shown in FIG. 18(a), the button 32 is moved to a position shown inFIG. 18(b). If the pressing pressure is released, it is maintained inthe state shown in FIG. 18(c). If the button 32 is pressed again in thestate shown in FIG. 18(c), it is restored to the state shown in FIG.18(a) through the state shown in FIG. 18(b). By pressing the button 32,it is possible to alternately switch to a state in which the valve body34 is settled on the valve seat 4f as shown in FIG. 18(a) and a state inwhich the valve body 34 is separated from the valve seat 4f as shown inFIG. 18(c).

In the above embodiment, a value of the spring constant of the coilspring 36 urging the valve body 34 toward the valve seat 4f is selectedsuch that it is contracted by a rise in pressure due to occurrence ofwater hammer upstream just after the opening valve 31 is closed. Thus,if an increase in pressure occurs just after the opening valve 31 isclosed, the valve body 34 leaves the valve seat 4f as shown in FIG.18(c) so that the flow route leading to the spray plate can be released.Consequently, as in the example shown in FIG. 15, it is possible torelease the rise of the pressure by allowing water to escape. That is,according to this embodiment, the opening valve 31 which is provided asa flow amount adjusting means is provided with a pressure cushioningfunction, so that the flow amount adjusting means and the pressurecushioning means are combined.

FIG. 1 shows an example in which the pressure adjusting means and thepressure cushioning means are integrally structured, and FIG. 18 showsan example in which the flow amount adjusting means and the pressurecushioning means are integrally structured. Of course, it is possible tostructure the pressure adjusting means, the flow amount adjusting meansand the pressure cushioning means integrally.

FIG. 19 shows an example in which an increase in pressure is suppressedby allowing water to escape through a spray plate in the shower head.

Unlike the previous examples, this shower head contains a button 42disposed at a front end of a main body 41 for opening and closing. Aplurality of valve holes (e.g., four holes at angular pitch of every 90°made in the valve seat 41a of the main body 41 are opened or closed, anda rotary type valve body 43 for switching the flow route is made tocommunicate with a button 42 by means of a cam shaft 43a and a rod 43b.The valve body 43 has two holes formed at an angular pitch of 180° whichmatch with two valve holes 41b in the valve seat 41a at the same time.

A mechanism applied to a shower head disclosed in Japanese Patentapplication No Hei 5-170398, proposed by the same applicant, and thelike can be applied directly for the opening operation and switch of aflow route by the valve 43 described above. If the handle 42 is pressedto the left side as viewed in FIG. 19, the valve body is turned at 90°until the valve body 43 is temporarily moved to the left and returned toits original position so that a combination between the valve body 43and the valve hole 41b can be changed.

Alternatively, a spray plate 44 connected to a main body 41 is formed byforming an annular chamber 44a on an external circumference of the mainbody 41, and by making spray holes 44b in this annular chamber 44a, andthen forming a discharging chamber 44c. The annular chamber 44a is madeto communicate with two valve holes 41b located diagonally in the radialdirection in the valve seat 41a, and the discharge chamber 44c is madeto communicate with a flow route from the other two valve holes througha communication route 41c. Consequently, if the button 42 is pressedonce, the flow route is changed to the annular chamber 44a. If thisbutton 42 is pressed once more, the flow route is changed to thedischarge chamber 44c. The structure is such that only when the flowroute is changed to the annular chamber 44c, can shower spray from thespray holes 44b be obtained and that no shower spray can be obtainedfrom the discharge chamber 44c. Then, the main body 41 is structured tohave an opening valve composed of the valve seat 41a and the valve body43.

The discharge chambers 44c have discharge holes 44d and a cylindricalguide 44e in the center thereof. In guide 44d is a relief valve body 45which can be moved vertically as viewed in FIG. 19. This relief valvebody 45 is urged toward a valve seat 46 located below a communicationroute 41c by means of a coil spring 47. At normal times, the reliefvalve 45 is settled on the valve seat 46 by this coil spring 47 so as toclose the valve hole 46a.

If the button 42 is pressed when the flow route is communicating withthe annular chamber 44a, as described previously, the valve body 43 isrotated so as to close the flow route to the annular chamber 44a, andthen the flow route is changed to a communication route 41c. In thecommunication route 41c, as shown in FIG. 19, the relief valve 45 issettled on the valve seat 46 at normal times so that shower spray fromthe main body 41 is stopped by the above operation. That is, a state inwhich the flow route is switched to the communication route 41ccorresponds to a state in which the valve is closed. Each time thebutton 42 is pressed, shower spray and stopping of water feeding arerepeatedly switched.

Like the example shown in FIG. 18, the value of the spring constant ofthe coil spring 47 is selected such that it is contracted and deformedby a pressure received by the relief valve body 45 because of a rise inpressure due to water hammer just after the valve is closed.Consequently, when the pressure upstream rises after the valve isclosed, the relief valve 45 leaves the valve seat 46 so as to open thevalve, and water upstream is allowed to escape through the dischargeholes 44d, thereby suppressing the rise in pressure.

FIG. 20 shows a practical embodiment in which an occurrence of waterhammer is suppressed by cushioning the closing velocity of the valve toeliminate a sudden shut-down of the flow route.

With respect to the same figure, a construction for the opening/closingoperation of the opening valve 9 is almost the same as that shown inFIG. 15, and the same reference numerals are utilized for the samemembers.

A spindle 9d has a rod 10a formed so as to protrude from a flange 9d-2on which a packing 9e is mounted, the rod 10a being integrally formed onthe same axis. At an end of the rod 10a a piston 10b is formed and onwhich a packing 10c is mounted over a circumference thereof.

A damper bore 4c having an opening axis coinciding with an axis of thespindle 9d is provided in an internal circumferential wall downstream ofthe valve seat 4b of the main body 4. This damper bore 4c has aninternal diameter allowing the packing 10c to slidably fit, and a smallhole 4d which is at the deepest bottom thereof communicating with thedownstream.

When the opening valve 9 is closed by turning a knob 9b-1 as in theprevious example, the spindle 9d is moved integrally with the guide ring9b in the closing direction of the valve. If the front end of thespindle 9d is structured to be of sufficient length such that the piston10b mounted thereon enters into the damper bore 4c before the packing 9eis settled on the valve seat 4b, the piston 10b is inserted into thedamper bore 4c at the same time as the packing 9e is moved in thedirection of the valve seat 4b.

Because mixing water is deposited in the damper bore 4c, if the piston10b enters, this mixing water is discharged out through the small hole4d. At this time, the piston 10b receives resistance by throttle of aflow route via the small hole 4d. Thus, the spindle 9d contracts thecoil spring 9i when the moving element 9c is moved in the closingdirection of the valve and the valve is closed at a velocity slower thanthat the motion of moving element 9c in the valveclosing direction.Thus, even if the knob 9b-1 is turned suddenly, the opening valve is notabruptly closed, thereby preventing an occurrence of water hammer due toa sudden shut-off of the flow route.

If the internal pressure upstream relative to the opening valve 5 isstill high after the valve is closed, an operation of separating thepacking 9e from the valve seat 4b by utilizing contraction of the coilspring 9i is enabled as indicated in the previous example, which iscapable of releasing high residual pressure after the valve is closed.

The coil spring 9i is capable of improving the operability by cushioningresistance from the spindle 9d as well as decelerating the spindle 9dand releasing pressure when the valve is closed. Furthermore, the coilspring 9i is not always necessary but it is permissible that a rod and apiston are provided on the spindle 5c of the opening valve 5 shown inFIGS. 11 and 14 such that the piston is receivable within the damperbore of the main body 4. In this case also, it is possible to prevent anoccurrence of water hammer by decelerating the valve closing speed.

FIGS. 22(a) and (b) are an example in which an occurrence of waterhammer is prevented by cushioning a shut-down of the flow route during atime interval from the start of valve closure to the completion thereof.

This example is essentially the same as the opening valve shown in FIGS.11 and 14, with the exception of the opening valve 5 and the packing 5h.The same reference numerals correspond to the same components and adescription thereof in detail is omitted.

A packing 11 provided at the front end of the spindle 5c comprises anannular seat 11a having substantially the same outside diameter as thatof a flange 5c-1 as shown in FIGS. 22(a) and (b), an end faceperpendicular to an axial line thereof and an insertion portion 11bcoaxially protruding from the annular seat a front end face which isinclined relative to the axial line. The annular seat 11a has a sizesufficient for covering the settling face of the valve seat 4b, and theinsertion portion 11b has an outside diameter allowing it to be insertedinto a valve hole 4b-1 surrounded by the valve seat 4b as shown in FIG.22(b).

Since the packing 11 has such a structure, if the valve is closed byturning the knob 5g from the valve opening state shown in FIGS. 22(a)and (b) to the valve closing state, first, the insertion portion 11b isinserted into the valve hole 4b-1. At this time, an entire portion ofthe insertion portion 11b is not inserted into the valve hole 4b-1 butis inserted gradually from a portion having a long length up to the tipto a portion having a short length. Thus, when the operation of closingthe valve is started, the area of the flow route from the valve hole4b-1 to the settling face of the valve seat 4b is changed so as to beslightly smaller. As the insertion portion 11b is completely insertedinto the valve hole 4b-1, a front end of the annular seat 11a approachesthe settling face of the valve seat 4b. Thus, during this process, thearea of the flow route is further decreased and, when the annular seat11a settles on the valve seat 4b the flow route is completely shut down.

By utilizing the shape of the packing 11, the operation of closing thevalve by throttling the area of the flow route gradually from a state inwhich the valve hole 4b-1 is completely opened is made possible in aninterval of time from the start of closing the valve to the completionthereof. Thus, it is possible to prevent an occurrence of water hammerby slightly closing the flow route, as in the example shown previouslyin FIG. 20.

Alternatively, the shape of the insertion portion 11b may be a cone aswell as a shape in which the front end thereof is cut diagonallyrelative to the axis as shown in FIGS. 22(a) and (b). In any case, ifthe valve is closed with the flow route area of such an annular sectionslightly decreasing when the insertion portion 11b is inserted into thevalve hole 4b-1, any type thereof may be utilized.

In the respective examples described above, when the valve is closed byoperating the main body 4 of the shower head, the increase in theinternal pressure downstream is absorbed by a pressure absorbingmechanism incorporated in the main body 4, and also absorbed by thepressure adjusting valve 21 connected to the proximal end of the hose 2as described in FIGS. 2 and FIGS. 3(a) and (b). Thus, the necessity ofabsorbing all pressure on the main body 4 of the shower head iseliminated, the space needed for pressure absorption can be reduced, andthe volume of the main body 4 does not have to be increased.

FIG. 23 is an example in which a pressure cushioning means for reducingwater hammer, which may occur when the control valve body 25 is closed,is provided in the mixing water exit 1b upstream of the pressureadjusting valve 21 shown in FIG. 9.

The pressure adjusting valve 21 shown in FIG. 23 is different only inthat a mechanism for adjusting the initial load of the spring 26 shownin FIG. 9 is not contained therein. The remaining construction is thesame. The pressure cushioning means shown in FIG. 14 is contained in anL-shaped joint 1c which is connected to the rear of the hot water/coldwater mixing plug 1 as a member for composing the mixing water exit 1bcommunicating with the hot water/cold water mixing plug 1.

As a pressure cushioning means, as in the example shown in FIG. 14, atube 1e filled with air is disposed in a block 1d incorporated in a bentportion of the joint 1c, and a small hole if is made in the block 1d toallow pressure from the flow route in the joint 1c to be transmitted tothe tube 1e.

By providing the block 1d containing such a tube 1e in the joint 1c,when the control valve body 25 is closed by receiving a rise in pressurein the hose 2 accompanied by the operation of stopping of water feedingto the shower head 3 side, an increase in pressure in the flow route inthe hot water/cold water mixing plug 1 is reduced by contraction anddeformation of the tube 1e. Thus, impact to the valve mechanism in thehot water/cold water mixing plug 1 and cold water/hot water pipingsystem in the building can be suppressed. Thus it is possible to reducenoises which otherwise occur in pipes.

As described above, according to the present invention, a pressureadjusting means for suppressing an increase in the internal pressure ofthe hose is provided at a portion which is on the fluid supply side andconnected to the proximal portion of the hose and, further, a pressurecushioning means for suppressing an increase in the internal pressurewhen the valve provided in the main body of the shower head is closed isalso provided in the main body of the shower head. Thus, when theopening valve is closed, water is stopped by the pressure adjustingmeans, and pressure is absorbed by expansion of the internal volume, andan increase in pressure is cushioned at the shower head side, therebyreducing the degree of change in the internal pressure to the hose.Consequently, repeated load on the hose is reduced and deterioration ofthe elasticity and damage of the sealing portion are prevented, therebyleading to an improvement in durability.

By incorporating a pressure cushioning means upstream of the pressureadjusting means, or by providing pressure adjusting means with a valvemechanism for cushioning an increase in pressure when water hammeroccurs, pressure load on the water plug is reduced so that continuedviability of the various parts of the shower apparatus composed of awater plug and hose is maintained.

The shower apparatus according to the present invention is capable ofpreventing an increase in the internal pressure of a flow route due towater hammer, which may occur when the flow route is closed or opened,in a piping system, in a water plug and building side, as well as in thehose up to the shower head.

Having described preferred embodiments of the invention with referenceto the accompanying drawings, it is to be understood that the inventionis not limited to those precise embodiments, and that various changesand modifications may be effected therein by one skilled in the artwithout departing from the scope or spirit of the invention as definedin the appended claims.

We claim:
 1. A shower apparatus for suppressing an increase in pressuredue to water hammer in a shower in which a supply fluid is provided to ashower head via a flow route extending from a supply to the shower head,the shower apparatus comprising:pressure adjusting means for adjusting apressure of the supply fluid; flow adjusting means for adjusting anamount of flow of the supply fluid, said pressure adjusting means beingdisposed upstream of said flow adjusting means, pressure cushioningmeans for cushioning an increase in an internal pressure of the flowroute which occurs when the flow route is closed by said flow adjustingmeans, said pressure cushioning means being disposed in communicationwith a portion of said flow route extending between said pressureadjusting means and said flow adjusting means to be operable as a flowroute system capable of cushioning an increase in the internal pressureof said portion of the flow route when said flow adjusting means isoperated to restrict flow through said shower head.
 2. A showerapparatus according to claim 1, wherein the pressure cushioning means isdisposed upstream of said pressure adjusting means.
 3. A showerapparatus according to claim 1 or 2, wherein said flow adjusting meansincludes an opening valve disposed in said shower head, said openingvalve including an operation portion.
 4. A shower apparatus according toclaim 3, wherein:said opening valve includes a valve body; the operationportion for the opening valve includes operating means for pressing saidvalve body to a valve closing position, said operating means beingdisposed to communicate with said valve body by means of a thrust lockmechanism; and said valve body can be set to an open position and theclosing position each time said operating means is pressed.
 5. A showerapparatus according to claims 1 or 2, wherein:the pressure adjustingmeans comprises a control valve body capable of alternately opening andclosing the flow route to the shower head and a pressure chamber formedon a side in which the control valve body is moved by receiving a flowroute internal pressure on a hose side thereof, said pressure chamberallowing said valve body to move in water-tight conditions; and aninternal volume of an internal flow route communicating with the hoseside can be expanded by moving of said control valve body to saidpressure chamber.
 6. A shower apparatus according to claim 5, whereinthe control valve body is structured such that when a stroke is takenthereby toward a valve seat to close said flow route, said control valveoperates to gradually reduce an amount of flow passing through a valvehole on said valve seat corresponding to an increase of a stroke amountof the control valve body.
 7. A shower apparatus according to claim 5,wherein:said control valve body includes a communication routeconnecting said control valve body and a space formed therebehind with avalve hole of the valve seat on which the control valve body is settledand a downstream of the valve hole, an internal diameter of saidcommunication route being in a range of about 0.3 mm-1.5 mm.
 8. A showerapparatus according to claim 5, wherein:said pressure adjusting meansincludes packing for blocking the flow route when the control valve bodyis settled thereon; and said packing has a hardness in a range of about40-70 degrees.
 9. A shower apparatus according to claims 1 or 2, whereinthe pressure adjusting means comprises:a valve hole made in a portion ofthe flow route extending between a fluid supply side and a hose side ofthe shower head; a control valve body which is located downstream of thevalve hole to make an end thereof wait, and which can be movedcoaxially; a pressure chamber for containing a proximal end portion ofsaid control valve body in water-tight condition; and an elastic meansfor urging said control valve body in a direction that it leaves saidvalve hole, said control valve body further having a communication routefor making a flow route on the side of the valve hole communicate withsaid pressure chamber so that said control valve body can be movedtoward said valve hole while expanding the internal volume of saidpressure chamber through a rise in pressure on the hose side, and saidcontrol valve body being further capable of moving between the front endof said control valve body and said valve hole in such a direction thatwill expand the internal volume of said pressure chamber even after saidvalve hole is closed by said control valve body.
 10. A shower apparatusaccording to claim 1 or 2, wherein the pressure cushioning means furthercomprises a pressure absorbing means for absorbing an increase inpressure by one of a deviation in position and a deformation thereof ina direction resulting in expansion of a capacity of the flow route byreceiving an increase in the internal pressure of the flow route.
 11. Ashower apparatus according to claim 10, wherein the pressure absorbingmeans is disposed upstream of the opening valve in the shower head andis constructed with a variable volume structure to expand a volume of aninternal flow route in the shower head accompanied by an increase in theinternal pressure of the flow route.
 12. A shower apparatus according toclaim 11, wherein the variable volume structure comprises:a borecommunicating with the internal flow route in the shower head; a pistonwhich is incorporated slidably in said bore in water-tight condition andwhich is made to wait in a portion communicating with the internal flowroute while receiving the internal pressure of the flow route; and anelastic means for urging said piston against a load of said internalpressure.
 13. A shower apparatus according to claim 11, wherein thevariable volume structure comprises a bore communicating with theinternal flow route in the shower head and a variable volume body whichis filled in said bore, and which can be contracted and deformed byexternal pressure.
 14. A shower apparatus according to claim 13 whereinthe variable volume body is one of an elastically deformable hollow tubeand a foamed substance.
 15. A shower apparatus according to claim 12,wherein an orifice is provided to throttle a flow route area in theinternal flow route, and where the bore is made to communicate with athroat portion of the orifice through a small hole.
 16. A showerapparatus according to claim 1 or 2 wherein the pressure cushioningmeans includes a pressure relief means for releasing an increase inpressure to outside air by receiving the increase in the internalpressure of the flow route so that it is one of deviated in position anddeformed in a direction of making the flow route open to the outsideair.
 17. A shower apparatus according to claim 16, wherein the pressurerelief means is structured as a water escape mechanism in which a valvebody of an opening valve is set to a valve opening positioncorresponding to an increase in pressure upstream when said valve bodyof the opening valve is located at a valve closing position.
 18. Ashower apparatus according to claim 17, wherein the opening valveemploys a valve switching mechanism in which a discharge end sidecommunicates when said opening valve is opened, and a flow route of thewater stopping side communicates when the valve is opened, and includesa water escape mechanism in a flow route which is in an end of the waterstopping side and communicates with the outside air.
 19. A showerapparatus according to claim 17, wherein the water escape mechanismallows the valve body of the opening valve to be separated from thevalve seat formed in the internal flow route by a stroke action in anaxial direction, and includes an elastic means for urging the valve bodyin the direction of closing the valve, a maximum repellent force of saidelastic means being slightly larger than the load of the minimumoperating pressure of the pressure adjusting means acting on the valvebody.
 20. A shower apparatus according to claim 1, wherein the flowadjusting means includes an opening valve, and the pressure cushioningmeans is structured in a form of a mild stopping mechanism for causing adelay from the start of closing the flow route by means of the openingvalve to a completion thereof.
 21. A shower apparatus according to claim20, wherein the opening valve includes a valve body and a valve seatformed in the internal flow route, and the mild stopping mechanism isstructured such that the valve body of the opening valve can be fixed toand separated from the valve seat by a stroke action in the axialdirection, the opening valve further including a damper bore in which afront end of the valve body can be inserted in water-tight condition inthe direction of closing the opening valve, said damper bore containinga small hole for discharging fluid inside thereof to the internal flowroute by inserting said valve body.
 22. A shower apparatus according toclaim 20, wherein the opening valve includes a valve body and a valveseat formed in the internal flow route, and the mild stopping mechanismis structured such that the valve body of the opening valve can be fixedto and separated from the valve seat by a stroke action in the axialdirection, and a flow of fluid passing through the valve hole isgradually reduced accompanied by an increase in the stroke amount of thevalve body in the direction of the valve seat.